Means for vaporizing liquids



June 28, 1932. H. H. DOW

MEANS FOR VAPORIZING LIQUIDS Filed Feb. 18, 1927 INVENTOR. He/5 e11 flflow BY Q' m 3' Q) ATTORNE Patented June 28, 1932 UNITED STA ES TEN O F CE IPANY; or ram-LAND, mcriieann conronnriolv or MICHIGAN r MEANS non vAPoRIzInG LIQUIDS:

fApplication filed February is, 1927. Serial No. 169,227.

Where liquids other than water are'heated in boilers or vaporizersof usual type, asfor instance in owerfplants operating with such a liquid e. g. volatilizable organic substances including oils and other hydrocarbons, and aromatic compounds such as diphenyl, diphenyl oxide, diphenylene, oxide, etc., in substitution for water for vapor generation, I have found that there may be a tendency to decomposition and that this occurs in particular where vapor bubbles form on the hot metal and the surface burns dry. The prevention of such tendency with liquids of quite high boilingpoint, or liquids of lower boiling point and under high pressure, is accordingly highly desirable, making possible the continuous use of such liquids as a practical basis for the generation of vapor for power by expansion in a heat engine, or for heating or re heating another power fluid in a power cycle, or still further for general use in indirect heating. a

To the accomplishment of the foregoing and related ends, the invention, then, consists of the features hereinafter fully described, and particularly pointed out in the claims, the following description and the annexed drawing setting forth in detail but a few of the various ways in which the principle of the invention may be employed.

In said annexed drawing Fig. 1 is a side elevational view and Fig. 2 is an end elevation of apparatus in accordance with the present invention; and Fig. 3 is an elevational detail.

The reference numeral 1 in the drawing designates a vapor-disengaging container having an outlet 2 to which an engine or other apparatus receiving or utilizing the disengaged vapors maybe connected, the detail of such being immaterial to the present'invention. In operative relation with the vapor disengaging container is a plurality of liquidheating containers comprising a plurality of tubes 3, the lower ends of which end inlower drums 4a, 4b, and 40 and the upper ends of which end respectively in upper drums or headers 5a, 5b, and'5c. The tubes 3 it will be understood are arranged in a furnace so as to receive direct heat, but for the purpose of illustration, and toav'oidnn'necessary complexity, the masonry of such a furnace chamber has been-omittedfrom the drawing. The liquideheatingcontainers are" maintained under pressure while in operation, but the vapor dlsengaging container 1 is free from such pressure. An. active circulation .or cycling of the liquid from the heaters to the vapornnannn'r H.now,-or M-IDLAND, MICHIGAN, Assreno'n 'ro 'rnnnow oHEMrcAI; comdisen'gager and back to the heaters and so on,

is also provided for. Connections 6a, 6b,

and extend betweenthe headers or drums 5a, 5.72 and 50 and one end ofthe" vapor-disengage'r 1, and lfrom'the other end offthe vapor-disengager, connections? a, 7?), and 7c extend" in turn to the lower drums 4a, 4b, and

40. q The pressure difierential mentioned may 'be realized in some cases by a suitable constricting of the connections between the respective elements, but more conveniently I 1:.

prefer to provide the pressure by arranging the vapor-disengager at a substantial elevation above the heaters, thereby attaining a hydraulic head to; the extent predetermined for in particular conditions. 'Acirculation of the liquid around through the respective elements results, it will be seen, from the thermosi'phonic effect of the relation of heat ed. and unheated elements, and if preferred,

thecirculation maybe furthered and accentuated' to any desired de ree by'setting in each orallofthe pipes 7a,; 7b, and 70 an impeller or pum for instance'fa pump of rotary type as shown at- 8, the pump casing constituting a portion of the connection 7. (7a, 7b, and 7 0,)

suitable means,-as a motor 10.. V

and the shaft 9 of thetrotor being. driven by pends upon the amount ofhead and circulation required under conditions encountered.

In general, doubling the" vertical distance bee tweenthe heater and vapor-disengager will double the differential pressure action,-an d also diminish by halfthe amount ofeirculation required to preventbubble formationv on the metal walls in the heater, and as will be' readily -un'dersto'o'd, t he particlular "require- 'ments as. to these willv'aryfwith the liquid beingg heated and vaporized, some of o the or? game liquids for instance of high molecular ibo ' weight and high boiling point requiring more uid-heating containers.

in the illustration, (Figs. 1 and 2), 5a, 4a,

and 5.7), 4?), and 50, to. That is, the upper headers 5a, 5b, 5c are in communication through respective connections 6a, 6b and 60 with the vapor-drum, and from the other end of the vapor-drum connections 7a, 7 b and7c 4 communicate respectively with thedrums 4a,

ll-band 40. 1 V As will be seen from the foregoing, with' the'tubes 3 of the liquid heaters subjected to larly inclined top and bottom drums, a plurality of vertical liquid-heating tubes connecting the top and bottom drum in each set, each such set of top and bottom drums being located at progressively higher levels, a vaporizing chamber connected with and elevated above'said sets of drums, the connections'between said chamber and drums including ducts between one end of the chamber and the upper ends of. the: respective top drums-and ducts between the other end of the chamber and the lower ends of the respective bottom drums, said vaporizing chamber being at a materially less pressure than the heating tubes andthe drums.

Signed by me this 6th day of February,

: HERBERT now;

7 furnace temperatures, and the contained liqv the vapor drum.

uid, for instance diphenyl' oxide, pyrene, plcene, etc., being under pressure and active movement from the circulation, vapor-bub ble formation on the metal walls here issuppressed, and the liquid is swept on up to the vapor-disengager 1. 'Here, under the diminattained, and vapors are'taken off at the outlet connection 2 to the further apparatus provided. Theunvaporized liquid is in turn 'ished pressure, vaporizing actively proceeds, to the extent engendered by the temperature ments, to be again heated and forwarded to In this manner'the requirements imposed V by liquid of a decomposiblecharacter may be readily met, and without impracticable complications of plant structure.

Other modes of applying the principle of the invention may be employed, change being made 7 as regards the details disclosed, providedthe steps or means stated in any of the following claims, or the equivalent of such, be

employe I r i I therefore particularly'point outand distinctly claim as my invention 1. In an apparatus for generating vapor, the combination of a plurality'of sets of top and "bottom drums, a' plurality of vertical liquid-heating" tubes connecting the top and bottom drum in each set, each such set of top and bottom drums being located at slightly overlapping progressively higher levels, and

a vaporizing chamber in common connected with and elevatedabove said sets of drums, the connections between said chamber and said drums including'ducts between one end end'of the chamber and the endl of the bottom drums. V

2;"In an apparatus for generating vapor,

corresponding the combination of a plurality of sets of'simi- 1 i 

